From 220bab24e5a58f1b5d66336427c0877329a5f88a Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Sat, 4 Jul 2020 13:15:12 +0200 Subject: [PATCH v2] Fix -Wcast-function-type warnings Discussion: https://www.postgresql.org/message-id/flat/20180206200205.f5kvbyn6jawtzi6s%40alap3.anarazel.de --- configure | 91 +++++++++++++++++++++++++++++++ configure.in | 2 + src/backend/utils/fmgr/dfmgr.c | 14 ++--- src/backend/utils/hash/dynahash.c | 9 ++- src/include/fmgr.h | 6 +- src/pl/plpython/plpy_plpymodule.c | 14 ++--- 6 files changed, 118 insertions(+), 18 deletions(-) diff --git a/configure b/configure index 2feff37fe3..9907637e31 100755 --- a/configure +++ b/configure @@ -5643,6 +5643,97 @@ if test x"$pgac_cv_prog_CXX_cxxflags__Wimplicit_fallthrough_3" = x"yes"; then fi + +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CC} supports -Wcast-function-type, for CFLAGS" >&5 +$as_echo_n "checking whether ${CC} supports -Wcast-function-type, for CFLAGS... " >&6; } +if ${pgac_cv_prog_CC_cflags__Wcast_function_type+:} false; then : + $as_echo_n "(cached) " >&6 +else + pgac_save_CFLAGS=$CFLAGS +pgac_save_CC=$CC +CC=${CC} +CFLAGS="${CFLAGS} -Wcast-function-type" +ac_save_c_werror_flag=$ac_c_werror_flag +ac_c_werror_flag=yes +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main () +{ + + ; + return 0; +} +_ACEOF +if ac_fn_c_try_compile "$LINENO"; then : + pgac_cv_prog_CC_cflags__Wcast_function_type=yes +else + pgac_cv_prog_CC_cflags__Wcast_function_type=no +fi +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext +ac_c_werror_flag=$ac_save_c_werror_flag +CFLAGS="$pgac_save_CFLAGS" +CC="$pgac_save_CC" +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_prog_CC_cflags__Wcast_function_type" >&5 +$as_echo "$pgac_cv_prog_CC_cflags__Wcast_function_type" >&6; } +if test x"$pgac_cv_prog_CC_cflags__Wcast_function_type" = x"yes"; then + CFLAGS="${CFLAGS} -Wcast-function-type" +fi + + + { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CXX} supports -Wcast-function-type, for CXXFLAGS" >&5 +$as_echo_n "checking whether ${CXX} supports -Wcast-function-type, for CXXFLAGS... " >&6; } +if ${pgac_cv_prog_CXX_cxxflags__Wcast_function_type+:} false; then : + $as_echo_n "(cached) " >&6 +else + pgac_save_CXXFLAGS=$CXXFLAGS +pgac_save_CXX=$CXX +CXX=${CXX} +CXXFLAGS="${CXXFLAGS} -Wcast-function-type" +ac_save_cxx_werror_flag=$ac_cxx_werror_flag +ac_cxx_werror_flag=yes +ac_ext=cpp +ac_cpp='$CXXCPP $CPPFLAGS' +ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5' +ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5' +ac_compiler_gnu=$ac_cv_cxx_compiler_gnu + +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main () +{ + + ; + return 0; +} +_ACEOF +if ac_fn_cxx_try_compile "$LINENO"; then : + pgac_cv_prog_CXX_cxxflags__Wcast_function_type=yes +else + pgac_cv_prog_CXX_cxxflags__Wcast_function_type=no +fi +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext +ac_ext=c +ac_cpp='$CPP $CPPFLAGS' +ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5' +ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5' +ac_compiler_gnu=$ac_cv_c_compiler_gnu + +ac_cxx_werror_flag=$ac_save_cxx_werror_flag +CXXFLAGS="$pgac_save_CXXFLAGS" +CXX="$pgac_save_CXX" +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_prog_CXX_cxxflags__Wcast_function_type" >&5 +$as_echo "$pgac_cv_prog_CXX_cxxflags__Wcast_function_type" >&6; } +if test x"$pgac_cv_prog_CXX_cxxflags__Wcast_function_type" = x"yes"; then + CXXFLAGS="${CXXFLAGS} -Wcast-function-type" +fi + + # This was included in -Wall/-Wformat in older GCC versions { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CC} supports -Wformat-security, for CFLAGS" >&5 diff --git a/configure.in b/configure.in index 0188c6ff07..2e05ce2e4d 100644 --- a/configure.in +++ b/configure.in @@ -498,6 +498,8 @@ if test "$GCC" = yes -a "$ICC" = no; then PGAC_PROG_CXX_CFLAGS_OPT([-Wmissing-format-attribute]) PGAC_PROG_CC_CFLAGS_OPT([-Wimplicit-fallthrough=3]) PGAC_PROG_CXX_CFLAGS_OPT([-Wimplicit-fallthrough=3]) + PGAC_PROG_CC_CFLAGS_OPT([-Wcast-function-type]) + PGAC_PROG_CXX_CFLAGS_OPT([-Wcast-function-type]) # This was included in -Wall/-Wformat in older GCC versions PGAC_PROG_CC_CFLAGS_OPT([-Wformat-security]) PGAC_PROG_CXX_CFLAGS_OPT([-Wformat-security]) diff --git a/src/backend/utils/fmgr/dfmgr.c b/src/backend/utils/fmgr/dfmgr.c index 9dff1f5e82..bd779fdaf7 100644 --- a/src/backend/utils/fmgr/dfmgr.c +++ b/src/backend/utils/fmgr/dfmgr.c @@ -95,7 +95,7 @@ static const Pg_magic_struct magic_data = PG_MODULE_MAGIC_DATA; * named funcname in it. * * If the function is not found, we raise an error if signalNotFound is true, - * else return (PGFunction) NULL. Note that errors in loading the library + * else return NULL. Note that errors in loading the library * will provoke ereport() regardless of signalNotFound. * * If filehandle is not NULL, then *filehandle will be set to a handle @@ -103,13 +103,13 @@ static const Pg_magic_struct magic_data = PG_MODULE_MAGIC_DATA; * lookup_external_function to lookup additional functions in the same file * at less cost than repeating load_external_function. */ -PGFunction +void * load_external_function(const char *filename, const char *funcname, bool signalNotFound, void **filehandle) { char *fullname; void *lib_handle; - PGFunction retval; + void *retval; /* Expand the possibly-abbreviated filename to an exact path name */ fullname = expand_dynamic_library_name(filename); @@ -122,7 +122,7 @@ load_external_function(const char *filename, const char *funcname, *filehandle = lib_handle; /* Look up the function within the library. */ - retval = (PGFunction) dlsym(lib_handle, funcname); + retval = dlsym(lib_handle, funcname); if (retval == NULL && signalNotFound) ereport(ERROR, @@ -165,12 +165,12 @@ load_file(const char *filename, bool restricted) /* * Lookup a function whose library file is already loaded. - * Return (PGFunction) NULL if not found. + * Return NULL if not found. */ -PGFunction +void * lookup_external_function(void *filehandle, const char *funcname) { - return (PGFunction) dlsym(filehandle, funcname); + return dlsym(filehandle, funcname); } diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c index 2688e27726..7c8039d0ef 100644 --- a/src/backend/utils/hash/dynahash.c +++ b/src/backend/utils/hash/dynahash.c @@ -398,7 +398,14 @@ hash_create(const char *tabname, long nelem, HASHCTL *info, int flags) if (flags & HASH_KEYCOPY) hashp->keycopy = info->keycopy; else if (hashp->hash == string_hash) - hashp->keycopy = (HashCopyFunc) strlcpy; + /* + * The signature of keycopy is meant for memcpy(), which returns + * void*, but strlcpy() returns size_t. Since we never use the return + * value of keycopy, and size_t is pretty much always the same size as + * void *, this should be safe. The extra cast in the middle is to + * avoid warnings from -Wcast-function-type. + */ + hashp->keycopy = (HashCopyFunc) (void (*) (void)) strlcpy; else hashp->keycopy = memcpy; diff --git a/src/include/fmgr.h b/src/include/fmgr.h index d349510b7c..f25068fae2 100644 --- a/src/include/fmgr.h +++ b/src/include/fmgr.h @@ -716,9 +716,9 @@ extern bool CheckFunctionValidatorAccess(Oid validatorOid, Oid functionOid); */ extern char *Dynamic_library_path; -extern PGFunction load_external_function(const char *filename, const char *funcname, - bool signalNotFound, void **filehandle); -extern PGFunction lookup_external_function(void *filehandle, const char *funcname); +extern void *load_external_function(const char *filename, const char *funcname, + bool signalNotFound, void **filehandle); +extern void *lookup_external_function(void *filehandle, const char *funcname); extern void load_file(const char *filename, bool restricted); extern void **find_rendezvous_variable(const char *varName); extern Size EstimateLibraryStateSpace(void); diff --git a/src/pl/plpython/plpy_plpymodule.c b/src/pl/plpython/plpy_plpymodule.c index e308c61d50..6356afbbd4 100644 --- a/src/pl/plpython/plpy_plpymodule.c +++ b/src/pl/plpython/plpy_plpymodule.c @@ -61,13 +61,13 @@ static PyMethodDef PLy_methods[] = { /* * logging methods */ - {"debug", (PyCFunction) PLy_debug, METH_VARARGS | METH_KEYWORDS, NULL}, - {"log", (PyCFunction) PLy_log, METH_VARARGS | METH_KEYWORDS, NULL}, - {"info", (PyCFunction) PLy_info, METH_VARARGS | METH_KEYWORDS, NULL}, - {"notice", (PyCFunction) PLy_notice, METH_VARARGS | METH_KEYWORDS, NULL}, - {"warning", (PyCFunction) PLy_warning, METH_VARARGS | METH_KEYWORDS, NULL}, - {"error", (PyCFunction) PLy_error, METH_VARARGS | METH_KEYWORDS, NULL}, - {"fatal", (PyCFunction) PLy_fatal, METH_VARARGS | METH_KEYWORDS, NULL}, + {"debug", (PyCFunction) (void (*) (void)) PLy_debug, METH_VARARGS | METH_KEYWORDS, NULL}, + {"log", (PyCFunction) (void (*) (void)) PLy_log, METH_VARARGS | METH_KEYWORDS, NULL}, + {"info", (PyCFunction) (void (*) (void)) PLy_info, METH_VARARGS | METH_KEYWORDS, NULL}, + {"notice", (PyCFunction) (void (*) (void)) PLy_notice, METH_VARARGS | METH_KEYWORDS, NULL}, + {"warning", (PyCFunction) (void (*) (void)) PLy_warning, METH_VARARGS | METH_KEYWORDS, NULL}, + {"error", (PyCFunction) (void (*) (void)) PLy_error, METH_VARARGS | METH_KEYWORDS, NULL}, + {"fatal", (PyCFunction) (void (*) (void)) PLy_fatal, METH_VARARGS | METH_KEYWORDS, NULL}, /* * create a stored plan -- 2.27.0